The same edit, three routes, wildly different clocks. The fast paths are genuinely usable — you’re trading faithfulness to the original composition, not raw quality.
| Route | Measured | Character |
|---|---|---|
| Qwen + 4-step Lightning LoRA | 15s | Conservative. Small surgical edits. |
| Flux.1 Kontext | 18s | Fast but looser — it changed our jacket’s cut and nudged the face. |
| Qwen-Image-Edit-2511, full | 57s | Faithful. Big changes without drift. |
Wiring the fast path
One node inserted, two numbers changed.
LoraLoaderModelOnly goes between your UNETLoader and the KSampler, with the 4-step Lightning LoRA
selected at strength 1.0. Then:
| Field | Normal | Lightning |
|---|---|---|
steps | 20 | 4 |
cfg | 2.5 | 1.0 |
Leaving CFG at 2.5 with a 4-step LoRA is the usual mistake — it produces a burnt, over-contrast image. The accelerator expects CFG at or near 1.
Which to reach for
- Iterating on wording? Lightning. Fifteen seconds means you can try eight phrasings in two minutes.
- Committed to the shot? Full mode. Take the fifty-seven seconds.
- Need a different model’s opinion? Kontext — but check the face afterwards.
Two more things worth knowing
Changing the camera angle is real and cheap. Asking for a three-quarter side view returned the same person, same room, same clothing, from a genuinely different angle in 42 seconds.
Text editing has a hard limit. It writes requested words correctly on flat, front-facing surfaces. On a tilted sheet of paper it rendered them mirrored. Front-facing only.
The settings, and what each one actually does
Four numbers in the KSampler carry an edit. These are the values we ran for every result below.
| Field | Value | Why |
|---|---|---|
steps | 20 | Below about 12 it stops respecting the instruction properly. |
cfg | 2.5 | The one people get wrong. On an edit model, high CFG doesn’t mean “obey me more” — it means “destroy the original.” Stay between 2 and 3. |
sampler_name | euler | Boring and reliable. |
scheduler | simple | Same. |
denoise | 1.0 | Surprising, but correct here: the encoder holds your original, not the noise level. |
seed | change it | When an edit half-works, same prompt + new seed is free. |